The topic covered in these last two classes was Situated Actions. In contrast to some of the other topics we have covered in the course, this is not really a theory or framework but more a highlighting of the importance of the specifics of a context to the interactions that happen there. An important concept that kind of sums this up is that actions are ‘situated’.

Practical Task

In groups, your task for this week is to analyze in detail an interaction between a person and a computer interface. Use Suchman’s framework to map out the actions and resources that are:

• Actions of the users.
  • Not available to the machine.
  • Available to the machine.
• Effects of the machine that are available to the user.
• What the design rational for these might be.

Points to look for in the exercise:

• What resources in the context other than the output of the machine do people use to help them accomplish their actions?
• Do plans play a role in the interaction? What kind?

For next week’s discussion, prepare a presentation of your findings.

Slides

Week 9 lecture slides are available.

Readings

• Chapter 6 ‘Situated Actions’ in Suchman, L.A., 1987. Plans and situated actions : the problem of human-machine communication, Cambridge ; New York: Cambridge University Press.

This week’s lecture was about Activity Theory. This theory originates with the psychology of Vygotsky. Compared to the other theories we have covered in the course, Activity Theory is probably closest to Distributed Cognition, in that it takes systems of activity (what Distributed Cognition would call functional systems) as the unit of analysis. However, there are important differences in the theories. A particularly significant difference is that whereas Distributed Cognition makes no distinction between people and artifacts, activity theory does. In activity theory the ability of people to act independently to effect change is an important idea. Another difference is that activity theory has more of a focus on the historical development of an activity system and pays more attention to processes of change and development.

Critical Questions

• Activity Theory has a lot of terminology and concepts. At the same time that this adds to the power of the theory, it may also make it more difficult to understand at first.

Practical Task

The practical task for this week was to think about what makes a good theory. In groups, students discussed the question and made a poster with suggestions for (1) what a theory is (2) what makes a good theory and (3) how the theories we have covered in the class compare in these respects. After the groups had discussed this amongst themselves for 15 minutes, we took a round where each group presented their poster to the rest of the class. We then combined the post-its, as shown in the picture above.

I have made a pdf poster based on the post-its that everyone put up on the board. I’ve taken the liberty of rearranging the post-its so related ideas from different groups are closer together. I’ve also color coded the post-its based on whether they talk about what a theory is, what makes a good theory, or about one of the theories we have covered in class.

Slides

Lecture slides are available

Oral Presentation Format

I also handed out a document explaining the format for the final oral presentation for the course. If you haven’t signed up for a time to give your presentation yet, you should email me or see me in class next week.

Readings

• Susanne Bodker, 2005. A Human Activity Approach to User Interfaces. Human Computer Interaction, 1989, v4, pp. 171-195.

• Nardi, B.A., 1995. Studying context: a comparison of activity theory, situated action models, and distributed cognition. In Context and consciousness: activity theory and human-computer interaction. Massachusetts Institute of Technology, p. 69-102.

Web Resources

• An extensive list of links around the topic of Activity Theory.
• Wikipedia article on Scandinavian Activity theory, which has a bit more detail than the general article about the application of Activity Theory to HCI.

This week’s class was a discussion of Gibson’s theory of Affordances based on the results of the practical exercise. Each group found three examples of affordances in products. As a group, we first looked at a still photograph of a product and discussed what it would afford for us and how we could see this from the picture. We then watched a video clip of the product in use and discussed whether we had interpreted the affordances of the product correctly and whether there were other affordances we had not considered.

Some interesting points that came up:

• Designing to hide affordances, the locket, hidden doors.
• Relation between affordances and knowledge of conventions. For example, red & blue color coding of faucet handles, use of an arrow on the medicine bottle lid.
• When to use the physical form to convey an affordance and when to rely on text. For example, the labelling of the days on the medicine dispenser.
• How does a product afford a range of levels of skill in the interaction. For example, the foosball table has relatively constrained and easy to interpret controls for a beginner (random twirling), but also affords refined interactions for a skilled player (deflecting off the wall).
• Even a simple product such as a table affords a wide range of activities. For example, sitting down to work at, dropping a coat on, leaving reminders on, eating a meal at, hiding under or even dancing on.
• It is also important to consider the whole posture of the body when thinking about the affordances. For example, an adjustable chair is much easier to adjust the height of when you are sitting in it than when you just operate the levers.

Do you have others that I have forgotten about?

Today’s lecture covered the theory of Affordances. This theory originates from the field of Ecological Psychology and the work of J.J. Gibson. It is best known in HCI circles through Norman’s book ‘The Design of Everyday Things.’ According to Gibson, affordances are:

“The affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or ill” (Gibson, p.127)

An important aspect of the idea is that an affordance describes a potential for action in the environment in relation to a person or animal. This has proven to be a very popular concept in design, perhaps because it deals with everyday aspects of perception and interaction and relates the usability of products to their physical form (in relation to a user) in a fairly straight-forward way.

Critical Questions

• The notion of affordances has been used in subtly different ways by different authors.
• Confusion betwen ‘Affordance’, ‘Convention’, and ‘Constraint’.
• Can we really talk about screen-based buttons affording clicking?

Practical Task

Your task for this week is to collect examples of affordances. In groups, see if you can find and shoot pictures and video of products that suggest the right (or wrong) actions in comparison to what they actually afford you. You should take a picture of the product by itself, and then a video of the product and action. Each group should find three examples.

Send me your examples by Friday and I will prepare a combined presentation, which we will use for a discussion in class.

For the discussion next week, discuss within your group why some things work and others are misleading.

Slides

Lecture slides are available

Readings

There are three readings for the topic of affordances. Copies were handed out in class.

• Norman, D.A., 1990. Chapter 4 “The design of everyday things” 1st ed., New York: Doubleday.
• Gibson, J.J., 1986. Chapter 4 “The Ecological Approach To Visual Perception” 1st ed., Lawrence Erlbaum.
• Gaver, W.W., 1991. Technology Affordances. In Conference on human factors in computing systems: Reaching through technology. New Orleans, Louisiana, United States: ACM Press, p. 79-84.

Web Resources

• A well written page that focuses on the differences between Norman’s use of ‘affordances’ and the original Gibsonian formulation.
• A page from Norman that clarifies his position on affordances as focussing on ‘perceived affordances’.

We had a discussion of the theory of Distributed Cognition that was presented in last week’s lecture. The class was in two parts. In the first part, groups presented the results of their practical exercise, where they tried to apply the ideas of Distributed Cognition to explaining the way that the library functions. In the second part, they did a little design exercise where they tried to apply these concepts to a new situation.

Distributed Cognition in the Library

There were seven presentations on the following topics:

• Finding a book (4 groups).
• Process of creating a new patron record.
• How the books are numbered.
• How the books are categorized.

Some interesting results of the groups analysis were:

• Identifying the role that the librarians played in helping people find books
• Librarians are specialized in particular areas.
• Use of pieces of paper, post-it notes, and even a mobile telephone to record notes about a book.
• Looking at activities at various levels of detail, from screen to screen transitions in the online catalog to how people wandered around the space of the library when looking for a book.

Problems Identified

Another interesting outcome of the exercise was that students identified several areas that seemed to present problems for library patrons. These might bear further investigation if one were involved in a re-design process in the library. These were:

• Difficulties associated with books that were located on a different campus,
• Seeming redundancy between the electronic and paper-based systems
• Apparent inconsistencies between the spatial organization of the books and the numbering system by which they are categorized
• Lack of adequate sign-age (an issue also raised by librarians).

Design Exercise

In the second half of the class, we ran a design exercise where students divided into three groups of five and spent some time discussing how they might use some of the insights gained from their study, or from the theory of Distributed Cognition for a re-design of some aspect of the library. Each group was given a different theme. These were ‘Finding your way’, ‘Making it orderly’, and ‘Identity’.

The ‘Finding your way’ group proposed a color coding scheme along with improved sign-age to make the different sections of the library more readily discernible by library patrons. Shelves would be colored depending on the category of the books that they contain. Librarians specialized in a field would wear a name-tag or shirt of the same color. Maps of the library would also display the colors and be printed on the floor so they could be more easily related to the physical space.

The ‘Making it orderly’ group also proposed using colors in connection with the categories of books. However in their system, rather than shelves and maps being color coded, they placed a diagonal stripe across the spines of all the books in a shelf. The stripe would go from the top of a book on the left side all the way down to the bottom of a book on the right side. The purpose of this was to make it apparent if a book was missing from the shelf or was out of place on the shelf. In either case, the diagonal line would be broken. This scheme also entailed a new way for stacking books in shelves based on their date of acquisition.

The ‘Identity’ group proposed a system where library patrons could leave reviews or ratings of books for others to access. The system would be implemented by adding pages to the current library website. An additional feature is that when patrons sign up with the library, they can give information about their interests and courses. This information is then used to make search results more relevant to the person searching.